Add placeholder to collection view when there are no items

Joey Lorich · Joey Lorich · commit 752a25db9ebf · 2014-04-30T16:57:11.000-04:00
diff --git a/EasyReader.xcodeproj/project.pbxproj b/EasyReader.xcodeproj/project.pbxproj
@@ -89,6 +89,10 @@
 		9D010F1718F83940001999EE /* EZRMenuFeedCell.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D010F1518F83940001999EE /* EZRMenuFeedCell.m */; };
 		9D010F1818F83940001999EE /* EZRMenuFeedCell.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D010F1518F83940001999EE /* EZRMenuFeedCell.m */; };
 		9D010F1918F83940001999EE /* EZRMenuFeedCell.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D010F1518F83940001999EE /* EZRMenuFeedCell.m */; };
+		9D0602131911970D009A94C0 /* UIView+PlaceholderAdditions.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D0602121911970D009A94C0 /* UIView+PlaceholderAdditions.m */; };
+		9D0602141911970D009A94C0 /* UIView+PlaceholderAdditions.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D0602121911970D009A94C0 /* UIView+PlaceholderAdditions.m */; };
+		9D0602151911970D009A94C0 /* UIView+PlaceholderAdditions.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D0602121911970D009A94C0 /* UIView+PlaceholderAdditions.m */; };
+		9D0602161911970D009A94C0 /* UIView+PlaceholderAdditions.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D0602121911970D009A94C0 /* UIView+PlaceholderAdditions.m */; };
 		9D06C6481901AE190029A233 /* EZRHomeSocialToolbarDataSource.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D06C6471901AE190029A233 /* EZRHomeSocialToolbarDataSource.m */; };
 		9D06C6491901AE190029A233 /* EZRHomeSocialToolbarDataSource.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D06C6471901AE190029A233 /* EZRHomeSocialToolbarDataSource.m */; };
 		9D06C64A1901AE190029A233 /* EZRHomeSocialToolbarDataSource.m in Sources */ = {isa = PBXBuildFile; fileRef = 9D06C6471901AE190029A233 /* EZRHomeSocialToolbarDataSource.m */; };
@@ -387,6 +391,8 @@
 		9D010F0F18F832C5001999EE /* EZRTestFlightService.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = EZRTestFlightService.m; sourceTree = "<group>"; };
 		9D010F1418F8392F001999EE /* EZRMenuFeedCell.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = EZRMenuFeedCell.h; sourceTree = "<group>"; };
 		9D010F1518F83940001999EE /* EZRMenuFeedCell.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = EZRMenuFeedCell.m; sourceTree = "<group>"; };
+		9D0602111911970D009A94C0 /* UIView+PlaceholderAdditions.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "UIView+PlaceholderAdditions.h"; sourceTree = "<group>"; };
+		9D0602121911970D009A94C0 /* UIView+PlaceholderAdditions.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "UIView+PlaceholderAdditions.m"; sourceTree = "<group>"; };
 		9D06C6461901AE190029A233 /* EZRHomeSocialToolbarDataSource.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = EZRHomeSocialToolbarDataSource.h; path = Home/EZRHomeSocialToolbarDataSource.h; sourceTree = "<group>"; };
 		9D06C6471901AE190029A233 /* EZRHomeSocialToolbarDataSource.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = EZRHomeSocialToolbarDataSource.m; path = Home/EZRHomeSocialToolbarDataSource.m; sourceTree = "<group>"; };
 		9D16D32618DB57D0001E9C38 /* EZRRegisterRoutesService.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = EZRRegisterRoutesService.h; sourceTree = "<group>"; };
@@ -619,6 +625,8 @@
 		2751F4D118DA02C100339C96 /* Categories */ = {
 			isa = PBXGroup;
 			children = (
+				9D0602111911970D009A94C0 /* UIView+PlaceholderAdditions.h */,
+				9D0602121911970D009A94C0 /* UIView+PlaceholderAdditions.m */,
 				9D010F0818F72F0B001999EE /* NSSet+CSSortingAdditions.h */,
 				9D010F0918F72F0B001999EE /* NSSet+CSSortingAdditions.m */,
 				9D5ACFBD18E5C787003CF3E7 /* UIImageView+EZRFeedImageAdditions.h */,
@@ -1384,6 +1392,7 @@
 				9D00DE86190816FF00A0C65F /* CLDSocialShareToolbar.m in Sources */,
 				9DFD89F818FC7D9300630CBF /* CSArrayTableViewDataSource.m in Sources */,
 				9D16D33E18DB7767001E9C38 /* EZRFeedUpdateService.m in Sources */,
+				9D0602151911970D009A94C0 /* UIView+PlaceholderAdditions.m in Sources */,
 				9D9CBAC318DCC52900532F8C /* EZRApplicationStyleService.m in Sources */,
 				9D639E7818E0A52300350B5F /* APIMockRequest.m in Sources */,
 				9D010F1818F83940001999EE /* EZRMenuFeedCell.m in Sources */,
@@ -1446,6 +1455,7 @@
 				9D00DE87190816FF00A0C65F /* CLDSocialShareToolbar.m in Sources */,
 				9DFD89F918FC7D9300630CBF /* CSArrayTableViewDataSource.m in Sources */,
 				9D16D33F18DB7767001E9C38 /* EZRFeedUpdateService.m in Sources */,
+				9D0602161911970D009A94C0 /* UIView+PlaceholderAdditions.m in Sources */,
 				9D9CBAC418DCC52A00532F8C /* EZRApplicationStyleService.m in Sources */,
 				9D639E7918E0A52300350B5F /* APIMockRequest.m in Sources */,
 				9D010F1918F83940001999EE /* EZRMenuFeedCell.m in Sources */,
@@ -1534,6 +1544,7 @@
 				9D00DE85190816FF00A0C65F /* CLDSocialShareToolbar.m in Sources */,
 				9DFD89F718FC7D9300630CBF /* CSArrayTableViewDataSource.m in Sources */,
 				9D9CBAC718DCC68A00532F8C /* EZRFeedUpdateService.m in Sources */,
+				9D0602141911970D009A94C0 /* UIView+PlaceholderAdditions.m in Sources */,
 				9D9CBAC818DCC68A00532F8C /* EZRApplicationStyleService.m in Sources */,
 				9D010F1718F83940001999EE /* EZRMenuFeedCell.m in Sources */,
 				9D9CBAC918DCC68A00532F8C /* Feed.m in Sources */,
@@ -1596,6 +1607,7 @@
 				9D00DE84190816F900A0C65F /* CLDSocialShareToolbar.m in Sources */,
 				9DFD89F618FC7D9300630CBF /* CSArrayTableViewDataSource.m in Sources */,
 				9D16D34E18DBA9E9001E9C38 /* APIRouter.m in Sources */,
+				9D0602131911970D009A94C0 /* UIView+PlaceholderAdditions.m in Sources */,
 				9D16D33D18DB7767001E9C38 /* EZRFeedUpdateService.m in Sources */,
 				9D9CBABF18DC826700532F8C /* EZRApplicationStyleService.m in Sources */,
 				9D010F1618F83940001999EE /* EZRMenuFeedCell.m in Sources */,
diff --git a/EasyReader/Application/Categories/UIView+PlaceholderAdditions.h b/EasyReader/Application/Categories/UIView+PlaceholderAdditions.h
@@ -0,0 +1,49 @@
+
+//
+//  UIView+PlaceholderAdditions.h
+//  uwithus
+//
+//  Created by Joseph Lorich on 3/10/14.
+//  Copyright (c) 2014 CSORGNAME. All rights reserved.
+//
+
+#import <UIKit/UIKit.h>
+
+/**
+ * Helpful additions for adding placeholders instead of an empty UIView
+ */
+@interface UIView (PlaceholderAdditions)
+
+
+#pragma mark - Methods
+
+/**
+ * Hides the current UIView and adds the given placeholder centered over where this view was
+ * Replaces any pre-existing placeholder views on this view
+ */
+- (void)hideAndInstantiatePlaceHolderWithView:(UIView *)placeholderView;
+
+/**
+ * Inserts the given placeholder centered inside this view.
+ * Replaces any pre-existing placeholder views on this view
+ */
+- (void)insertCenteredPlaceholderView:(UIView *)placeholderView;
+
+/**
+ * Removes all placeholder views and shows the original view
+ */
+- (void)removePlaceholderViewAndShow;
+
+/**
+ * Generates a plain placeholder with a title and replaces the current view with it
+ */
+- (void)hideAndInstantiatePlaceHolderWithTitle:(NSString *)title;
+
+
+#pragma mark - Properties
+
+/// An array of currently existing placholder views
+@property (nonatomic, retain) UIView *placeholderView;
+
+
+@end
diff --git a/EasyReader/Application/Categories/UIView+PlaceholderAdditions.m b/EasyReader/Application/Categories/UIView+PlaceholderAdditions.m
@@ -0,0 +1,123 @@
+//
+//  UIView+PlaceholderAdditions.m
+//  uwithus
+//
+//  Created by Joseph Lorich on 3/10/14.
+//  Copyright (c) 2014 CSORGNAME. All rights reserved.
+//
+
+#import "UIView+PlaceholderAdditions.h"
+#import <objc/runtime.h>
+#import <Block-KVO/MTKObserving.h>
+
+
+static void *PlaceholderPropertyKey = &PlaceholderPropertyKey;
+
+@implementation UIView (PlaceholderAdditions)
+
+- (UIView *)placeholderView {
+  return objc_getAssociatedObject(self, PlaceholderPropertyKey);
+}
+
+- (void)setPlaceholderView:(NSArray *)placeholderView {
+  objc_setAssociatedObject(self, PlaceholderPropertyKey, placeholderView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+}
+
+
+/**
+ * Generates a frame centered over another frame
+ */
+- (CGRect)centeredFrame:(CGRect)frame overFrame:(CGRect)overFrame
+{
+  return CGRectMake(
+                    overFrame.origin.x + overFrame.size.width/2.0 - frame.size.width/2.0,
+                    overFrame.origin.y + overFrame.size.height/2.0 - frame.size.height/2.0,
+                    frame.size.width,
+                    frame.size.height
+                    );
+}
+
+/**
+ * Updates the placeholderView frame on parent frame change
+ */
+- (void)frameDidChange:(id)sender
+{
+  if (self.placeholderView)
+  {
+    CGRect frame = [self centeredFrame:self.placeholderView.frame overFrame:self.frame];
+    [self.placeholderView setFrame:frame];
+  }
+}
+
+- (void)insertCenteredPlaceholderView:(UIView *)placeholderView
+{
+  [self removeAllObservations];
+  [self observeProperty:@"bounds" withSelector:@selector(frameDidChange:)];
+  
+  CGRect frame = [self centeredFrame:placeholderView.frame overFrame:self.frame];
+  [placeholderView setFrame:frame];
+  
+  [self addSubview:placeholderView];
+  
+  if (self.placeholderView)
+  {
+    [self.placeholderView removeFromSuperview];
+  }
+  
+  self.placeholderView = placeholderView;
+
+}
+
+- (void)hideAndInstantiatePlaceHolderWithView:(UIView *)placeholderView
+{
+  [self removeAllObservations];
+  [self observeProperty:@"bounds" withSelector:@selector(frameDidChange:)];
+  
+  
+  CGRect frame = [self centeredFrame:placeholderView.frame overFrame:self.frame];
+  [placeholderView setFrame:frame];
+  
+  [self setHidden:YES];
+  [[self superview] addSubview:placeholderView];
+  
+  if (self.placeholderView)
+  {
+    [self.placeholderView removeFromSuperview];
+  }
+  
+  self.placeholderView = placeholderView;
+}
+
+- (void)removePlaceholderViewAndShow
+{
+  [self removeAllObservations];
+  [self.placeholderView removeFromSuperview];
+  
+  self.placeholderView = nil;
+  
+  [self setHidden:NO];
+}
+
+
+- (void)hideAndInstantiatePlaceHolderWithTitle:(NSString *)title
+{
+  UIView *placeholder = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 280, 40)];
+  
+  UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 280, 40)];
+  [label setTextColor:[UIColor lightGrayColor]];
+  [label setTextAlignment:NSTextAlignmentCenter];
+  [label setLineBreakMode:NSLineBreakByWordWrapping];
+  [label setNumberOfLines:3];
+  [label setFont:[UIFont fontWithName:@"HelveticaNeue" size:14.0f]];
+
+  [label setText:title];
+  
+  [placeholder addSubview:label];
+  
+  
+  [self hideAndInstantiatePlaceHolderWithView:placeholder];
+}
+
+
+
+@end
diff --git a/EasyReader/Application/Controllers/EZRHomePageControlDataSource.m b/EasyReader/Application/Controllers/EZRHomePageControlDataSource.m
@@ -14,7 +14,7 @@ @implementation EZRHomePageControlDataSource
 
 - (NSInteger)numberOfPagesForPageControl
 {
-    return [[EZRCurrentFeedsProvider shared].feedItems count];
+    return [[EZRCurrentFeedsProvider shared].visibleFeedItems count];
 }
 
 @end
diff --git a/EasyReader/Application/Controllers/Home/EZRHomeViewController.m b/EasyReader/Application/Controllers/Home/EZRHomeViewController.m
@@ -41,6 +41,7 @@
 #import "EZRGoogleAnalyticsService.h"
 
 #import "CCARadialGradientLayer.h"
+#import "UIView+PlaceholderAdditions.h"
 
 @interface EZRHomeViewController()
 
@@ -290,6 +291,14 @@ - (void)selectedFeedDidChange:(NSNotification *)notification
  * Updates the data source when the feed items change
  */
 - (void) visibleFeedItemsDidChange:(EZRCurrentFeedsProvider *)currentFeedService visibleFeeditems:(NSArray *)visibleFeedItems {
+    if (visibleFeedItems.count == 0) {
+        self.scrollView_vertical.scrollEnabled = NO;
+        [self.collectionView_feedItems hideAndInstantiatePlaceHolderWithTitle:@"No feed items are available at this time."];
+    } else {
+        [self.collectionView_feedItems removePlaceholderViewAndShow];
+        self.scrollView_vertical.scrollEnabled = YES;
+    }
+    
     if (self.currentFeedItem) {
         lastSelectedFeedItem = self.currentFeedItem;
     }
@@ -304,15 +313,7 @@ - (void) visibleFeedItemsDidChange:(EZRCurrentFeedsProvider *)currentFeedService
     } else if ([visibleFeedItems count] > 0){
         [self resetWebView];
         
-        NSIndexPath *destinationIndexPath;
- 
-//        if (self.currentPageIndex < [visibleFeedItems count]) {
-//            destinationIndexPath = [NSIndexPath indexPathForRow:[visibleFeedItems count] -1 inSection:0];
-//        } else {
-//            destinationIndexPath = [NSIndexPath indexPathForRow:self.currentPageIndex - 1 inSection:0];
-//        }
-        
-        destinationIndexPath = [NSIndexPath indexPathForRow:0 inSection:0];
+        NSIndexPath *destinationIndexPath = [NSIndexPath indexPathForRow:0 inSection:0];
         
         [self.collectionView_feedItems scrollToItemAtIndexPath:destinationIndexPath atScrollPosition:UICollectionViewScrollPositionLeft animated:NO];
         [self loadURLForFeedItem:visibleFeedItems[0]];
diff --git a/EasyReader/Application/Controllers/Menu/MenuDataSources/EZRMenuUserFeedDataSource.m b/EasyReader/Application/Controllers/Menu/MenuDataSources/EZRMenuUserFeedDataSource.m
@@ -59,8 +59,8 @@ - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(N
     
     if (indexPath.row == 0) {
         cell = [tableView dequeueReusableCellWithIdentifier:self.reusableCellIdentifier];
+        ((EZRMenuFeedCell*)cell).feed = nil;
         ((EZRMenuFeedCell*)cell).label_name.text = @"All Feeds";
-        
         if (self.currentFeedsProvider.currentFeed == nil) {
             cell.selected = YES;
         }

Original file line number	Diff line number	Diff line change
`@@ -14,7 +14,7 @@ @implementation EZRHomePageControlDataSource`
`14`	`14`
`15`	`15`	`- (NSInteger)numberOfPagesForPageControl`
`16`	`16`	`{`
`17`		`- return [[EZRCurrentFeedsProvider shared].feedItems count];`
	`17`	`+ return [[EZRCurrentFeedsProvider shared].visibleFeedItems count];`
`18`	`18`	`}`
`19`	`19`
`20`	`20`	`@end`
Original file line number	Diff line number	Diff line change
`@@ -59,8 +59,8 @@ - (UITableViewCell )tableView:(UITableView )tableView cellForRowAtIndexPath:(N`
`59`	`59`
`60`	`60`	`if (indexPath.row == 0) {`
`61`	`61`	`cell = [tableView dequeueReusableCellWithIdentifier:self.reusableCellIdentifier];`
	`62`	`+ ((EZRMenuFeedCell*)cell).feed = nil;`
`62`	`63`	`((EZRMenuFeedCell*)cell).label_name.text = @"All Feeds";`
`63`		`-`
`64`	`64`	`if (self.currentFeedsProvider.currentFeed == nil) {`
`65`	`65`	`cell.selected = YES;`
`66`	`66`	`}`